The present invention relates to a preset position (preset state) display apparatus for displaying the preset position of an adjustment portion adjusted in a change in printed matter or the like in a printing press, and a preset position adjusting apparatus for automatically setting the preset position of the adjustment portion.
In a conventional printing press, the set state of each adjustment portion is set in an appropriate state for printed matters (preset state) in a change in printed matter or the like.
For example, in the delivery unit of a sheet-fed rotary press, the set state of each adjustment portion such as the position of a sheet release cam or a sucker wheel, the rotational speed of a fan, and an air volume are set to the preset states by operating a dial or lever corresponding to the adjustment portion.
The delivery unit has an important function of properly delivering and stacking printing paper, and this function is evaluated as paper alignment performance. The paper alignment performance is determined by the set state of each adjustment portion such as the position of the sheet release cam or the sucker wheel, the rotational speed of the fan, and the air volume. The set state is adjusted every time the printed matter is changed, thereby obtaining desired paper alignment performance.
Conventionally, however, the preset state for each adjustment portion is determined by experiences and skills of an operator every time the printed matter is changed. For this reason, variations are caused by the degrees of skills of the operators. The same preset state for the same printed matter as in the last operation is hardly reproduced, and quality such as printing condition or paper alignment in the delivery unit is unstable. Adjustment requires a lot of time, which varies with the degrees of skills of the operators. Therefore, a skilled operator is inevitably required.
A technique is disclosed in Japanese Patent Laid-Open No. 61-291138 titled "METHOD AND APPARATUS FOR SETTING OF INK POT IN EARLY PERIOD FOR OFFSET PRINTING". According to this technique, when the same opening degree of an ink pot for the same printed matter as in the last operation is to be set, the last setting recorded in a magnetic card is displayed. The opening degree of the ink pot is manually set to the displayed preset state.
In this case, however, using a magnetic card as a data storage medium causes following problems.
1 Since a stand-alone magnetic card is used, the data may be lost due to mechanical or magnetic damage of the card.
2 The magnetic card requires a preparing operation, and it takes much time. Safekeeping/management of the card is also needed.
3 A reader and a writer for the magnetic card are required, which causes an increase in cost.